Get workflow statuses

Model Generator attempts to solve your testing needs for generating data.
Should be able to create random data in your DB, you may specify any attributes you like with named parameter.
For data that is dependent on other data, those dependencies will be generated for you if unspecified.

Added ability for transition to find all possible statuses in a workflow.
Useful for when editing a workflow.

Closing #19 since this builds on top of that.